How do viruses reproduce?

Viruses reproduce by infecting living cells, which is a fundamental aspect of their life cycle. Unlike living organisms such as bacteria or plants, viruses lack the cellular machinery necessary for self-replication. They do not have the ability to grow or reproduce independently; instead, they must hijack a host cell to replicate their genetic material and produce new viral particles.

Once a virus enters a host cell, it utilizes the cell's machinery to replicate its genetic material and synthesize the components needed to assemble new virions. This process often results in the destruction or dysfunction of the host cell, which is why viral infections can lead to illness in the host organism.

The other options do not accurately describe the reproductive method of viruses. For example, viruses do not divide on their own since they are not living organisms and lack the necessary structures and processes for such division. Additionally, while some bacteria can replicate independently and may even be susceptible to viral infections (in the case of bacteriophages), viruses do not replicate within bacteria. Lastly, viruses do not form spores, which is a reproductive process typical of certain fungi and some plants, allowing them to survive in adverse conditions. Thus, infecting living cells is the definitive method by which viruses reproduce.